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What's the difference between VARCHAR and CHAR?
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CHAR
Used to store character string value of fixed length.
The maximum no. of characters the data type can hold is 255 characters.
It's 50% faster than VARCHAR.
Uses static memory allocation.
VARCHAR
Used to store variable length alphanumeric data.
T...
Why does String.valueOf(null) throw a NullPointerException?
according to the documentation, the method String.valueOf(Object obj) returns:
4 Answers
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What's the point of malloc(0)?
...ht_be_zero) perhaps could have their uses, although again you have to take extra care not to treat a NULL return as a failure if the value is 0, but a 0 size is supposed to be OK.
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Store boolean value in SQLite
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Which is better in term of performance! true/false as strings or 0/1 integer?
– Muhammad Babar
Aug 9 '15 at 13:38
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How to convert a string to integer in C?
I am trying to find out if there is an alternative way of converting string to integer in C.
12 Answers
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Convert a character digit to the corresponding integer in C
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If, by some crazy coincidence, you want to convert a string of characters to an integer, you can do that too!
char *num = "1024";
int val = atoi(num); // atoi = ASCII TO Int
val is now 1024. Apparently atoi() is fine, and what I said about it earlier only applies to me (on O...
Pad a string with leading zeros so it's 3 characters long in SQL Server 2008
I have a string that is up to 3 characters long when it's first created in SQL Server 2008 R2.
17 Answers
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Why does Oracle 9i treat an empty string as NULL?
...efore there was a SQL standard, Oracle made the design decision that empty strings in VARCHAR/VARCHAR2 columns were NULL and that there was only one sense of NULL (there are relational theorists that would differentiate between data that has never been prompted for, data where the answer exists but ...
Setting up FTP on Amazon Cloud Server [closed]
...at you already have an EC2 instance created and have associated an Elastic IP Address to it.
Step #1: Install vsftpd
SSH to your EC2 server. Type:
> sudo yum install vsftpd
This should install vsftpd.
Step #2: Open up the FTP ports on your EC2 instance
Next, you'll need to open up the F...
Converting string to byte array in C#
...e array was created like this:
byte[] bytes = Encoding.ASCII.GetBytes(someString);
You will need to turn it back into a string like this:
string someString = Encoding.ASCII.GetString(bytes);
If you can find in the code you inherited, the encoding used to create the byte array then you should b...